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Diffstat (limited to 'Documentation/i2c/chips/adm1026')
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diff --git a/Documentation/i2c/chips/adm1026 b/Documentation/i2c/chips/adm1026 deleted file mode 100644 index 473c689..0000000 --- a/Documentation/i2c/chips/adm1026 +++ /dev/null @@ -1,93 +0,0 @@ -Kernel driver adm1026 -===================== - -Supported chips: - * Analog Devices ADM1026 - Prefix: 'adm1026' - Addresses scanned: I2C 0x2c, 0x2d, 0x2e - Datasheet: Publicly available at the Analog Devices website - http://www.analog.com/en/prod/0,,766_825_ADM1026,00.html - -Authors: - Philip Pokorny <ppokorny@penguincomputing.com> for Penguin Computing - Justin Thiessen <jthiessen@penguincomputing.com> - -Module Parameters ------------------ - -* gpio_input: int array (min = 1, max = 17) - List of GPIO pins (0-16) to program as inputs -* gpio_output: int array (min = 1, max = 17) - List of GPIO pins (0-16) to program as outputs -* gpio_inverted: int array (min = 1, max = 17) - List of GPIO pins (0-16) to program as inverted -* gpio_normal: int array (min = 1, max = 17) - List of GPIO pins (0-16) to program as normal/non-inverted -* gpio_fan: int array (min = 1, max = 8) - List of GPIO pins (0-7) to program as fan tachs - - -Description ------------ - -This driver implements support for the Analog Devices ADM1026. Analog -Devices calls it a "complete thermal system management controller." - -The ADM1026 implements three (3) temperature sensors, 17 voltage sensors, -16 general purpose digital I/O lines, eight (8) fan speed sensors (8-bit), -an analog output and a PWM output along with limit, alarm and mask bits for -all of the above. There is even 8k bytes of EEPROM memory on chip. - -Temperatures are measured in degrees Celsius. There are two external -sensor inputs and one internal sensor. Each sensor has a high and low -limit. If the limit is exceeded, an interrupt (#SMBALERT) can be -generated. The interrupts can be masked. In addition, there are over-temp -limits for each sensor. If this limit is exceeded, the #THERM output will -be asserted. The current temperature and limits have a resolution of 1 -degree. - -Fan rotation speeds are reported in RPM (rotations per minute) but measured -in counts of a 22.5kHz internal clock. Each fan has a high limit which -corresponds to a minimum fan speed. If the limit is exceeded, an interrupt -can be generated. Each fan can be programmed to divide the reference clock -by 1, 2, 4 or 8. Not all RPM values can accurately be represented, so some -rounding is done. With a divider of 8, the slowest measurable speed of a -two pulse per revolution fan is 661 RPM. - -There are 17 voltage sensors. An alarm is triggered if the voltage has -crossed a programmable minimum or maximum limit. Note that minimum in this -case always means 'closest to zero'; this is important for negative voltage -measurements. Several inputs have integrated attenuators so they can measure -higher voltages directly. 3.3V, 5V, 12V, -12V and battery voltage all have -dedicated inputs. There are several inputs scaled to 0-3V full-scale range -for SCSI terminator power. The remaining inputs are not scaled and have -a 0-2.5V full-scale range. A 2.5V or 1.82V reference voltage is provided -for negative voltage measurements. - -If an alarm triggers, it will remain triggered until the hardware register -is read at least once. This means that the cause for the alarm may already -have disappeared! Note that in the current implementation, all hardware -registers are read whenever any data is read (unless it is less than 2.0 -seconds since the last update). This means that you can easily miss -once-only alarms. - -The ADM1026 measures continuously. Analog inputs are measured about 4 -times a second. Fan speed measurement time depends on fan speed and -divisor. It can take as long as 1.5 seconds to measure all fan speeds. - -The ADM1026 has the ability to automatically control fan speed based on the -temperature sensor inputs. Both the PWM output and the DAC output can be -used to control fan speed. Usually only one of these two outputs will be -used. Write the minimum PWM or DAC value to the appropriate control -register. Then set the low temperature limit in the tmin values for each -temperature sensor. The range of control is fixed at 20 °C, and the -largest difference between current and tmin of the temperature sensors sets -the control output. See the datasheet for several example circuits for -controlling fan speed with the PWM and DAC outputs. The fan speed sensors -do not have PWM compensation, so it is probably best to control the fan -voltage from the power lead rather than on the ground lead. - -The datasheet shows an example application with VID signals attached to -GPIO lines. Unfortunately, the chip may not be connected to the VID lines -in this way. The driver assumes that the chips *is* connected this way to -get a VID voltage. |
